M3.8 Earthquake 36 km S of Sand Point, Alaska — September 23, 2023
2023-09-23 20:38:15 UTC (2023-09-23) · approx. 9:38 AM UTC-11 local
On September 23, 2023 at 20:38 UTC, a magnitude 3.8 shallow crustal earthquake struck 36 km S of Sand Point, Alaska, at a depth of 40.5 km and coordinates 55.0068°, -160.4471°.
Physical scale: An earthquake of magnitude 3.8 releases seismic energy equivalent to roughly 7.6 metric tons of TNT. Empirical fault-scaling laws (Wells & Coppersmith, 1994) estimate the subsurface rupture length at approximately 252 m — a useful intuition for the size of the slip patch on the fault.
ShakeMap — predicted shaking intensity
Modeled ground-motion intensity contoured on the Modified Mercalli scale (MMI). Computed by the USGS from the moment-tensor solution and regional ground-motion prediction equations.
Source: U.S. Geological Survey ShakeMap. View interactive ShakeMap on USGS
Earthquake Details
-160.4471°E
Technical Information
Nearby Earthquakes (Last 7 Days)
Common Questions
How strong was the magnitude 3.8 earthquake near Sand Point, Alaska?
The magnitude 3.8 earthquake that struck 36 km S of Sand Point, Alaska on September 23, 2023 at 20:38 UTC had a depth of 40.5 km. For context, this was a minor earthquake typically detected only by instruments.
Were there aftershocks?
Aftershock activity is monitored continuously by the USGS. Aftershock sequences from magnitude 3.8 earthquakes can continue for several days and gradually diminish over time.
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Understanding This Data
Magnitude 3.8 earthquakes are typically only recorded by instruments.
Authoritative source: USGS event page (event ID: us7000kxpw). All scientific values on this page are sourced verbatim from the USGS feed.
Cite this page: EarthquakeTracker.org. (2023, September 23, 2023). M3.8 Earthquake 36 km S of Sand Point, Alaska — September 23, 2023. Retrieved December 2, 2023 from https://www.earthquaketracker.org/earthquakes/event/us7000kxpw/